The polymerization of ethylene and ethylene copolymers using various methods and catalysts is known in the art. For blow molding applications, it is important for the polyethylene resin to exhibit a relatively high melt flow ratio. Melt flow ratio as used herein is the ratio of high load melt index to melt index. The melt index in g/10 min. at 190.degree. C. is run according to ASTM method D-1238 65T using a weight of 2.16 kg. The high load melt index in g/10 min. at 190.degree. C. is run according to ASTM method D-1238 65T using a weight of 21.6 kg.
Melt flow ratios can be increased by various compounding methods. However, these methods increase the final cost of the resin, require additional steps and adversely affect certain desired properties of the resin.
It would therefore be desirable to provide a simple economical polymerization process capable of preparing ethylene homopolymers and copolymers having a high melt flow ratio while still maintaining other desired properties.